Socket for vacuum tubes, etc.



Sept. 13, 1938. M. ALDEN I 2,129,725

SOCKET FOR VACUUM TUBES, ETC

Filed Nov. 28, 1934 aill l I L aianswer/om Patented Sept. 13, 1938UNITED STATES PATENT OFFICE 12 Claims.

My invention relates particularly to electrical connecting devicescommonly called sockets which are adapted to receive the prongs of tubesor plugs.

One object of my present invention is to provide a type of constructionadapted to accommodate tubes or plugs having a large number of prongssuch as six or more. Such devices are for many reasons limited in sizeso .that very little room is left between adjacent contacts. As a resultof this cramping or crowding of a large number of contacts into a smallspace, difilculties of manufacture and use arise.

One object therefore of my invention is to provide a. type ofcontact'which occupies a mini- 'mum space.

Another object is to provide a type of contact which can be made at aminimum cost.

Another object is to provide a construction which will permit ofrepeated insertion and withdrawal of prongs for a long period of timewithout deterioration or injury.

One object is to provide a contact which will not fail or become set anddistorted by careless insertion of tube prongs and the like.

Another object is to provide a construction which will afford aneffective electrical connection.

In carrying out the invention the body of the socket is formed of twoparts of insulation with an inner chamber containing the contacts, onepart of the body having entrance passages for the prongs leading in tothe contacts. The contacts themselves are flat and shaped something likeatuning 'fork, the ends of which are held in place in the body and theprongs of the tube or plug are introduced through the openings in onepart of the body into the spaces between the fingers of the contacts.

Fig. 1 is a plan view of my invention.

Fig. 2 is a longitudinal sectional view of the same, showing, however,only one contact in place.

Fig. 3 is a bottom view of the upper part of the socket and showing twocontacts in place but in cross section with tube prongs inserted.

Fig. 4 is a fragmentary view showing one of the contacts and an insertedprong in a fragment of the' socket.

Fig. 5 is a perspective view of one of the contacts.

The parts I and 8 of the socket body are a socket embodying formed ofinsulating material, preferably the part "I being molded to the shapedesired and the stitutes a convenient means for the attachment 'for thetips of the fingers l5. preferably of rectangular outline but slightlyrivet 9 and one part is provided with means for attaching the socket toa suitable support as for instance the anchorage lugs Ill.

'I'he'body isprovided with an interior chain- 10 ber I I containing thecontacts and one part of the body is provided with a number of passagesl2 through which the prongs of the tube or plug are inserted.

Each contact consists of one or more stamp- 3 ings M of sheet metal andeach contact has a pair of fingers I5, l5 spaced apart from each otherfor the reception of a tube prongbetween thefri. The opposite end l6 ofeach contact con- 20 or anchorage of the circuit wire in any suitablemanner.

The body part I is provided with recesses il Each recess is larger thanthe tips of .the contact fingers so as to loosely hold the tips of thecontacts in place.

The'insulating disc 8 is provided with passages l8 through which theheads of the contacts project. The neck IQ of each contact is positionedin .one of these passages l8 and the contact is provided with a shoulder20 which withstands the longitudinal thrust of the contact when a tubeprong is inserted.

The entrance between the tips of the fingers l5, I5 is tapered orinclined at 2| to facilitate introduction of a tube prong. The prong 22represents a typical plug or tube prong adapted to be inserted into thespace between the fingers l5, 15. In many cases it has been foundespecially advantageous to provide two members for each contact as shownin Figs. 3 and 4. These two contacts are laid side by side and looselypositioned in the insulation. The pair of contacts afford especiallyeiiective electrical connections in that when the cylindrical base ofthe tube prong is inserted, the two contacts tend to separate from eachother as shown in Fig. 4 and thus embrace the tube prong along fourlines where the inner edges of the fingers grip the metal of the prong.In this way it is possible to obtain tight contact capable of yieldingwithout straining the metal.

The advantages of this type of construction 55.

will be especially appreciated when it is recalled that at the presenttime tube prongs are frequently irregularly located and are sometimesbent.

In my improved form of construction the contacts readily adjust or adaptthemselves to the position of the prongs even if the prongs aremisplaced or bent.

My present form of contact is designed for high speed manufacture andyet the contacts are bound to be very accurate as no bending is re- 75tact being of flat metal so that its expansion is quired.

Applicants construction has been tested for a long period of timewithout destruction or damage.

The material of the contacts is preferably harder than that of the tubeprongs so that the prongs themselves usually become worn before thecontacts. As an extra precaution the contacts are preferably silverplated. This type of contact is especially desirable in view of the factthat the conductivity is not materially interfered with even if thecontacts become somewhat oxidized. The brass contacts, even after thesilver is apparently worn ofi the surface, are effective.

By the construction and arrangement shown it is practically impossibleto insert the prongs of a tube or plug in such a way as to strain orinjure the contacts.

It should be understood that although the invention relates primarily tothe flat contact structure and method of support, the socket may have inaddition any well known form of contact anchored for instance in arecess 23.

The flat contacts take up so little space that several of them can beinserted in an ordinary socket in the space that would be required for asingle contact of the ordinary type. The loosely mounted fiat contactsaflord in efiect a floating support for the tube and its prongs. Thesecontacts it will be seen lend themselves especially to the complicatedpattern of combination sockets and adapters. In fact these flatfork-like contacts may be used in combinations where the conventionaltype of contacts are impracticable.

I claim:

1. In a socket, an insulating body formed of two parts one of which isprovided with an interior chamber and having prong passages passingthrough the face of one part only and leading into the chamber, twofork-like flat contact plates having spaced apart fingers the tips ofwhich are loosely positioned alongside of one of the pasterior chamberand having prong passages leading into the chamber, and having slitsextending for at least a portion of the length of said passages, afork-like fiat contact having spaced apart fingers the tips of which arepositioned alongside of one of the passages and are situated with themajor portion of their material lying in said slits, saidcontact havinga connecting portion projecting through the other part of the body forexternal electrical connection, said conin the plane of the metal when9. prong enters therein.

3. A socket structure as described in claim 2, in which said fork-likecontact member is free to ,fioatingly move within the limits of saidslits and said passages whereby it may adjust itself to irregularitiesof an entering prong.

4. A flat one-piece vacuum tube socket. contact formed of sheet metallying substantially in a single plane and comprising two spaced fingershaving tip portions with interior edges tapering towards theirextremities, a connecting lug at one end and a shoulder portion adjacentsaid lug, said fingers being materially greater in size in the directionof said plane than in their thickness, said fingers being spaced apartfor substantially all their length beyond said tip portions a distanceslightly less than the thickness of a prong to be inserted therein,whereby said prong upon complete insertion will engage and spread saidfingers so that their inner edges become substantially parallel and thelongitudinal axis of the prong and the longitudinal direction of thefingers lie substantially in one plane and so that the points of contactform substantially straight lines.

5. A flat one-piece vacuum, tube socket contact for use to receive arod-like tube connector prong, said contact-being formed of sheet metaland having two flat arms joined together at one end of each arm andlying in a common plane throughout their lengths and spaced apart adistance slightly less than the diameter of a vacfor use to receive arod-like tube connector prong, said contact being formed of sheet metaland having two fiat fingers joined together at one end lying in a commonplane throughout their lengths and spaced apart a distance slightly lessthan the diameter of a vacuum tube prong, said fingers being formed soas to embrace the opposite sides of said prong in such fashion that thelongitudinal axis of said prong will lie substantially wholly betweensaid fingers, and said contact having a soldering lug at the rear end,the cross sectional area of said fingers being less near their point ofjuncture than at any other point along their length which is formed soas to make contact with said tube prong, when said prong is completelyinserted into said fingers.

7. In a socket, an insulating body having prong passages leading throughone face only thereof, each passage being provided for at least part ofits length with lateral extensions of slot-like form, a flat fork-likemetallic contact having spaced apart fingers the tips of which arepositioned alongside one of said passages and are loosely held in saidextensions, said contact also having a connecting portion passingthrough the opposite face of said body.

8. A vacuum tube socket having a body formed of insulating material withpassages for the. reception of the tube prongs and relatively narrowgrooves extending laterally from opposite sides of at least a part ofthe length of each passage, iiat fork-like contactmembers looselysupported in said body each member having its fingers spacedapart fromeach other with their tips positioned in said grooves on opposite sidesof a passage for the tube prong, the inner edges of the fingers of eachcontact member being inclined to provide a tapered entrance for a tubeprong, said body having portions constituting means positioning a partof each contact member remote from the tips of the fingers and eachcontact member having a head portion projecting from the body andconstituting means for the attachment of a connecting wire thereto.

9. A socket having an insulating body provided with passages forreceiving tube prongs and grooves longitudinally extending along aportion of the length of each passage, fiat fork-like contact makingmembers having fingers on opposite sides of said passages and having thetips of the fingers wider than the rest of the fingers, whereby saidcontacts can be inserted from the ends of said passages remote from theends wherein the tube prongs enter and whereby said tips lie at leastpartly in said grooves and are loosely supported in said passages in aposition suitable for receiving the tube prongs, said contact membersalso being provided with portions projecting from said body, forconnection of external wires thereto.

10. In a socket, an insulating body portion formed with a roof portion,a skirt portion and a base portion having passages, said portionsforming an interior chamber, said roof portion having prong passagesleading into the chamber and also having slots extending along at leasta portion of the prong passages, a fork-like fiat contact plate composedof spaced apart fingers materially larger in their flat dimension thanin their thickness and a connecting portion, said contact plate beingdisposed in said chamber with the tips of its fingers lying at leastpartly in said slots so that the space between the fingers is inalignment with the prong opening and its connecting portion is extendingexteriorly of the base through the passages therein.

11. In a socket, an insulating body portion formed with a roof portion,a skirt portion and a base portion forming an interior chamber, saidroof portion having prong passages leading into the chamber and alsohaving slots extending along at least a portion of the prong passages,said base portion having passages opposite to said prong passages, afork-like fiat contact plate in said chamber, said contact platecomposed of spaced apart fingers materially largerin their flatdimension than in their thickness, positioned in alignment with saidprong passages and having the tips of its fingers lying in said slots,said plate having a connecting portion extending through the passages inthe base for external electrical connection, and shoulders formed onsaid contact plate adapted to engage the inside of the base to preventdisplacement of the contact plate.

12. A vacuum tube socket including contact members fashioned in afork-like form and cut from sheet metal, the spaced fingers of the forklying in a common plane and the inwardly facing edges of said forkconstituting the prong engaging contact portions of the structure over aportion of their length materially greater in extent than theirthickness, the cross sectional area of said fingers being less neartheir point of juncture than at any other point along the prong engagingcontact portions of said structure, when a prong is fully insertedtherein.-

MILTON ALDEN.

